Widget Titles

Hello I am trying to remove the lines on either side of my widget titles in my sidebar. I have deleted the following code from my style.css section, however the lines are still appearing. Any insights as to how I can fix this. Also is there a way I can make those widget titles appear in a box and increase their font size? Thank you very much for your assistance. My site is https://cookingwithchika.com

@media(min-width:991px) {
.widget-title {
color: #000;
display: inline-block;
background: #fff;
margin: auto;
position: relative;
padding: 10px;
}
aside {
position: relative;
text-align: center;
}
aside ul,
aside p {
text-align: left;
}
aside:before {
background: #000;
height: 1px;
content: '';
display: block;
top: 46px;
margin: auto;
width: 196px;
right: 0;
left: 35px;
padding: 0 25%;
position: absolute;
}